VOA慢速英语:Two Events Blamed for Dinosaur Deaths(翻译)

Dinosaurs ruled the Earth for about 160 million years.Then they disappeared.
恐龙统治地球长达1.6亿年。然后它们灭绝了。

Scientists have argued for years about what killed off the dinosaurs.
关于恐龙灭绝的原因，科学家们争论了多年。

Was it the huge volcanic eruption 66 million years ago in what is now India?That explosion changed the Earth’s climate in a major way.Then, just 150,000 years later, a meteorite from space struck the coast of Mexico.This also caused changes to the climate.
是6600万年前在如今的印度发生的火山喷发造成它们的灭绝吗？那次火山喷发很大程度上改变了地球的气候。15万年之后，来自太空的陨石击中墨西哥海岸。这也造成了气候的变化。

Both catastrophic events happened during what is called the Cretaceous Period in Earth’s history.
这两大灾难性事件发生在白垩纪时期。

Scientists have long debated which event caused the dinosaurs to disappear? One reason the debate continued was the failure of the scientists to find a perfect window from which to look into the past.
科学家们一直以来都在争论哪一个事件造成了恐龙的灭绝。争论一直持续的原因是无法找到记载过去的资料。

But now, researchers say they have found a clear record of what happened.
如今研究人员表示他们发现了清晰记录过去的线索。

The new evidence comes from Seymour Island -- an Antarctic island near the southern most part of South America.The researchers reported their findings in Nature Communications.
新证据来自西摩岛，这是南极的一个岛屿，靠近南美的最南部。研究人员在《自然通讯》发表了他们的研究发现。

Sierra Peterson is a paleoclimatologist with the University of Michigan.She studies the climate from ancient times.To do that, she uses evidence from rocks and the fossilized remains of ancient creatures.
Sierra Peterson是密歇根大学的古生物气象学家。她研究古时候的气候。她利用岩石和古生物化石标本进行相关研究。

“The timing of the volcano and the meteorite are quite close together.”
“火山爆发和陨石坠落的时间非常接近。”

Peterson says that with only 150,000 years separating them, physical evidence of the two events is so close together in the rock record that it is hard to tell them apart.But it is easier at the Antarctic island.
Peterson表示二者发生的时间只相差15万年，岩石中所能显露的证据都非常接近，很难将这两个事件区分开来。但是在这个南极岛上就容易得多。

“At Seymour Island there’s 40 meters separating those two events.So we can really separate the influences of each one, and that’s why we can see the climatic impacts of both as two separate events.”
“在西摩岛，有40米的距离可以区分这两个事件。所以我们能够看出两个事件的不同影响，也能够看出两个事件分别对气候变化造成的影响。”

“It makes sense why people thought it was one or the other.And really they were both right.”
“也能看出来为什么人们觉得造成恐龙灭绝的原因是这两个事件中的一个。确实他们说的都对。”

That is Andrea Dutton, a geochemist with the University of Florida.When Dutton was a student, she studied fossilized shells from Seymour Island. She examined them in an effort to understand ancient climate changes.But the results were unclear and difficult to understand.
说这话的是佛罗里达大学的地球化学家Andrea Dutton。当她还是学生时，她就研究西摩岛的贝壳化石。想要通过对贝壳化石的研究了解古代气候变化。但结果很不明确，很难理解。

The fossils were put in storage until Peterson showed up with a new technique.It identifies the kinds of carbon molecules in a shell. These molecules depend strongly on the temperature of the water when that layer of shell was formed.
这些化石一直存放着，直到Peterson带着新技术出现。该技术可以鉴别贝壳内的碳分子类型。这些分子的形成依赖于贝壳层形成时水的温度。

What this meant is that, for the first time, scientists were able to find out the temperature record during the dinosaurs’ last days.What they discovered was that things got hot -- not once, but twice.
这就意味着科学家首次找到恐龙灭绝前的温度记录。他们发现，温度上升了两次，而非一次。

”At the time when the volcanism began, we found a rapid warming spike that had not been seen before.And we also found at the boundary itself, when the meteorite hit, we also saw another warming spike.”
“在火山开始喷发的那段时间，我们发现温度迅速飙升，这是之前从未发现的。我们还发现，当陨石坠落，同样温度迅速升高。”

It is what the researchers are calling a “one-two punch.”First, the dinosaurs were hit by acid rain and volcanic dust after the huge volcanic eruption.Dutton says things got a lot worse with the sudden temperature increase that followed.
研究人员将其称为“连环出击“。首先在火山喷发后恐龙遭遇酸雨和火山灰的袭击。Dutton说之后随着温度突然升高，恐龙的生存环境愈加恶劣。

“Certainly these clams that we were studying and the other fauna in this system, they had experienced temperatures this warm earlier in the Cretaceous.But what happened here is the temperature increase was so fast that it was a large stress that they weren’t able to adapt that quickly to the large temperature change.”
“我们研究的这些蚌类及其他动物群，在白垩纪之前也经历过高温。但白垩纪时温度升高的速度之快，给它们造成了巨大压力，它们无法适应巨大的温度变化。”

Dutton says she and Peterson are not necessarily saying that the warming is what killed everything at the time.But it could have made things worse.It could have been responsible for part of the dinosaurs disappearing.
Dutton说她和Peterson没有说变暖是造成物种灭绝的原因。但它加速了生存环境的恶化。这也是恐龙灭绝的部分原因。

After that, the creatures that survived the first warming spike suffered another blow — a huge rock from space hitting Earth. That impact also caused a jump in temperatures.
那之后，这些生物逃过第一次高温，却遭遇了第二次因陨石撞击地球引起的温度上涨。这使得温度发生巨大的变化。

So why is it important to know about how and why the dinosaurs died off so long ago?
所以为什么研究恐龙灭绝的原因和方式很重要？

Peterson and Dutton suggest people should pay close attention to their work.They say the effects of fast climate change in the Cretaceous period are similar to what scientists are seeing now from climate change.
Peterson 和Dutton建议人们密切关注他们的工作。他们说白垩纪时期气候迅速变化造成的影响，类似于科学家对如今气候变化的影响研究。

Peterson says the volcano eruption before the meteorite increased pressure on Earth’s environment.In that same way, the carbon dioxide gas emissions from human activities are affecting the environment today.
Peterson说陨石撞击前的火山喷发给地球环境造成了很大压力。同样，人类活动造成的二氧化碳排放也影响了今天的环境。

“We are already seeing extinctions and certain organisms being under a lot of environmental stress, reduced habitat, things like that. All of the same things we are observing today would have been in play in the Cretaceous as well. And so, you know, I guess fingers crossed for no meteorite impact.”
“我们目睹了物种的灭绝，某些物种生活在巨大的环境压力下，栖息地锐减。我们如今所观察到的所有事情，都曾经在白垩纪上演。所以我只想十指紧扣，祈祷不会发生陨石撞击的状况。”

And so it seems we might have a lot to learn from the dinosaurs’ disappearance.
所以看来我们能从恐龙灭绝中学到很多。

I’m Anne Ball.
Anne Ball为您报道。